Assessment of Prevalence and Heterogeneity of Meso- and Microplastic Pollution in Icelandic Waters

Surface water samples were collected using a low-tech aquatic debris instrument (LADI) at six nearshore locations on the north and northwestern coasts of Iceland to investigate the prevalence of mesoplastic (5–10 mm) and microplastic (0.3–5 mm) in the region. This sampling strategy involved sampling each transect three times for a total of 18 samples collected in order to assess uncertainties related to heterogeneous distribution of plastic in surface waters. Samples in all six nearshore locations contained meso- and/or microplastic, though concentrations were highly variable. Visual, physical, and FTIR analyses were performed on 71 suspected plastic particles collected, confirming and identifying 40 of those particles as one of six types of plastic: polypropylene (PP), polyethylene (PE), high-density polyethylene (HDPE), polyester, low-density polyethylene (LDPE), and polyvinyl chloride (PVC). Lines originating from fishing gear were the most prevalent types of plastic detected across the samples. This study is among the first to quantify and identify microplastic particles collected in Icelandic nearshore surface waters.